360 block limits

I don't disagree with that, however, people with carburetors certainly have more than just a "base tune". I've seen a lot and I mean a LOT of high end builds leave with nothing more than what the car cranked up with. All because they would not pay extra for a tune....and that's just stupid.
Yep, and plenty of cars leave shops with the carb bolted on straight out of the box from Summit, with it's basic tune in it and so-so gas mileage.
No one should be sending an EFI car out of a shop without a good usable tune in it. If they are not doing that, then they have no business fitting the stuff.